[Evolvedx27]

Does anyone have a Roto fab and catback exhaust on stock tune? If so, how is the car running? I'm really looking into this but concerned about throwing codes/needing a tune.

[BlaqWhole]

You shouldn't need a tune with those items. Catback is next on my list but not for a couple months. I have RF, Katech ported TB, and VTC.

[Evolvedx27]

Originally Posted by BlaqWhole

You shouldn't need a tune with those items. Catback is next on my list but not for a couple months. I have RF, Katech ported TB, and VTC.

I just don't wanna be the test mule lol

[edc901]

Rotofab and full Stainless Works catback (which deleted second cats) Runs fine. I haven't had it to the 1/4 yet, but so far so good. I don't really feel any power increase, but it sounds good.

I think a ported throttle body will be next but then I'm done. I don't trust anyone around here for tuning and not in the mood for shipping(or driving) the car somewhere far away.

[Evolvedx27]

Originally Posted by edc901

Rotofab and full Stainless Works catback (which deleted second cats) Runs fine. I haven't had it to the 1/4 yet, but so far so good. I don't really feel any power increase, but it sounds good.

I think a ported throttle body will be next but then I'm done. I don't trust anyone around here for tuning and not in the mood for shipping(or driving) the car somewhere far away.

Good to hear. Anyone else have these mods?

[NerdWerx]

Honest question, here.

I read somewhere, quite a while ago (not sure where it was) that some people looked at an aftermarket exhaust on a ZL1 as a complete waste and in some cases, a backward change. They argued that the exhaust that comes stock on the car was amazing, and tuned to near perfection on the car. And that any changes would only offer minimal performance difference (2-5 hp) or even a loss in some cases.

Other than the crazier sounds offered by an aftermarket exhaust, do they really offer a substantial performance benefit? Why do people get them?

I'm genuinely curious on this. I will hopefully be picking up either a vette or a ZL1 at some point in the not-so-distant future. One aspect of the choice that is important to me is upgradeability. I want a car that I can modify for more power over time.

[edc901]

Originally Posted by NerdWerx

Other than the crazier sounds offered by an aftermarket exhaust, do they really offer a substantial performance benefit? Why do people get them?

No. Felt no gains. Just bought for #ballastatus and sound. Keep factory NPP to save money. Maybe just do a second cat delete.

[NerdWerx]

Originally Posted by edc901

No. Felt no gains. Just bought for #ballastatus and sound. Keep factory NPP to save money. Maybe just do a second cat delete.

Haha! Good stuff, man! Would love to hear it.

[soceur77]

its funny i was just thinking about this last night and started seriously considering an axel back vs a cat back system I already ordered and will most likely return. To sort of answer the op question, if you check out the Z06 guys most of them leave the stock muffler in place, so that says alot about the suitcase muffler at least.

[brantley847]

Originally Posted by edc901

No. Felt no gains. Just bought for #ballastatus and sound. Keep factory NPP to save money. Maybe just do a second cat delete.

Was the sound increase that significant? I've heard a few owners say they were disappointed even with valves open. I'm coming from headers and a cam in my 5th gen and while I probably won't do the cam again I'd like to run long tubes through additional cat back system if the stocks open valves weren't that big of an improvement.

Absolutely couldn't care any less about gains

Curious if headers with stock exhaust valves open would be sufficient

[edc901]

Originally Posted by brantley847

Was the sound increase that significant? I've heard a few owners say they were disappointed even with valves open. I'm coming from headers and a cam in my 5th gen and while I probably won't do the cam again I'd like to run long tubes through additional cat back system if the stocks open valves weren't that big of an improvement.

Absolutely couldn't care any less about gains

Curious if headers with stock exhaust valves open would be sufficient

It's not much louder, it's mostly a change in tone. I think the loudness gain is from the second cat delete. I had already bought the kit and tried to sell it. But then I didn't want to have to worry about shipping costs cause of the weight so I went ahead and installed it. If I were to do it again, I'd just do a second cat delete and be done with it.

[Evolvedx27]

Gains don't usually come from replacing the catback on any vehicle... if theirs any gains it's less than 5hp/tq. But for added sound and weight savings it's kinda worth it to me... on another note I also find it hard to believe that the secondary cats, and crushed sections in exhaust don't make the exhaust restrictive... in the future the entire exhaust is getting done anyway so.

[Evolvedx27]

Originally Posted by edc901

It's not much louder, it's mostly a change in tone. I think the loudness gain is from the second cat delete. I had already bought the kit and tried to sell it. But then I didn't want to have to worry about shipping costs cause of the weight so I went ahead and installed it. If I were to do it again, I'd just do a second cat delete and be done with it.

Now I've heard people wishing they went the catback route instead of the cat delete because sound barely changed.

[Evolvedx27]

Originally Posted by edc901

It's not much louder, it's mostly a change in tone. I think the loudness gain is from the second cat delete. I had already bought the kit and tried to sell it. But then I didn't want to have to worry about shipping costs cause of the weight so I went ahead and installed it. If I were to do it again, I'd just do a second cat delete and be done with it.

I don't know man. Phastek has some videos on YouTube of a zl1 with stainless works exhaust. Sounds a lot louder to me.